If your integrations aren’t on API 3.0, please update them
before
April 2. More
information

Mailchimp API 3.0

We’ve rebuilt Mailchimp's API from the ground up to be simpler, more consistent, and truly RESTful.
With version 3.0, it’s easier than ever to sync email activity with your database, link campaign stats to your database, and test different calls and endpoints before pushing to production.